Telescope.



PATBNTBD MAY 2, 1905.

C. P. DIBGKMANN.

TELESGOPE.

APPLIGATION FILED APR.2.1904.

2 SHEETS-SHEET 1.

PATENTED MAY 2, 1905.

o. P. DIEGI'IMANN.

TELESCOPE.

APPLICATION FILED APR.2.1904.

2 SHEETS-EHEBT 2.

STATns PAT NT Patented May 2, 1905.

TELESCOFE.

SPECIFICATION forming part of Letters Patent No. 788,823, dated May 2, 1905.

Application filed April Z, 1904. Serial No. 201,245-

To (1,7/7/ whom, t Indy concern:

Be it known that I, CARL F. DIECKMANN, a citizen ot' the United States, residing at Buffalo, in the county of Erie and State oi' New York, have invented new and uset'ul Improvements in Telescopes, of which the following is a specilication.

This invention relates more particularly to that class of telescopes in which prisms are employed Afor erecting the image and in which one of the prisms is adjustable relatively to the other, so that the instrument can be focused without changing the relation between the objective and the eyepiece. The improvements are especially desirable for operaglasses, but are generally applicable to optical instruments employing' a telescope.

One object et my invention is to improve the adjusting device of the movable prism, with a view of rendering it simple in construction and convenient oit' operation.

Another object is to provide-an improved arrangement of the prisms which when employed in an opera-glass or similar binocular instrument permits the instrument to be made comparatively short, light, and compact.

The invention has the further objects to improve the construction of the eyepiece-tubes, so that they can be shortened when the instrument is not in use, and to improve the construction ot' the instrument in' other respects.

ln the accompanyingI drawings, consisting ot' two sheets, Figure l is a side elevation of an opera-glass embodying my invention. Fig. 2 is a Jfront view thereof. Fig. 3 is an end view of the instrument. Fig. 4 is a longitudinal section of one ot' the main members of the instrument, the plane ot' the section being in line 4 4, Fig. 2. Fig. 5 is an enlarged interior view of the rear plate oi' one of the telescope-casings and the prisms mounted thereon. Fig. 6 is an external view oi said plate. Fig. 7 is a cross-section, on a reduced scale, in line Y 7, Fig. 5. Fig. 8 is an enlarged longitudinal section of the i'ront portion of the hinge which connects the two main parts of the instrument. Fig. 9 is adiagrammatic perspective view ot' the objective, prisms, and eyepiece ot' one ot' the telescopes. Fig. l() is an enlarged longitudinal section ot' one of the eyepieces. Fig. 1l is a sectional elevation el a Held-glass containing a moditied Form of the invention. Fig. l2 is a longitudinal section of the telescope of a transit or other surveyinginstrumentembodyingtheinvention. Fig'. 13 is a fragmentary longitudinal section showing another modilication ot' the adjusting means of the movable prism.

Similar letters of reference indicate corresponding parts throughout the several views.

The opera-glass illustrated in Figs. l te l() is of the type in which the two main members lof the instrument are hinged together, so as to allow adjustment between the eyepieces to suit the pupilary' distance et' the observers eyes. In the present instrument each ot'- these main members comprises an oblong casing A, closed on all sides and containing the prisms, an eyepiece B, having the usual eye-lens B, and an objective-tube O, containing the usual objective-lens c.

'.lhe hinge between the main members may be of any suitable construction, but is preterably constructed as follows: The front and rear plates A A2 ot' each casing A are provided at.` their inner ends with eyes or perforated lugs d, which overlap those ot' the other casing, and these eyes are pivotally connected by a pintle or screw E, havinga milled head e, for the purpose hereinafter described. This screw passes through the rear eyes et' the hinge and is held against endwise movement by a nut c. The opposite end ot' the screw is reduced and unthreaded and turns in a bearing-sleeve (f2, seated in the Vfront hingeeyes and having at its inner end a flange et, which hears against the inner one of said eyes. rlhe projecting front end oi this sleeve is reduced and screw-threaded to receive a clamping-nut Spring-washers a are preferably interposed between the nuts e' e and the hinge-eyes.

The objective-tubes O may be screwed or Y IOO screwed or otherwise secured in an opening in the front plate A', while its outer section ',whicb forms the shell of the eyepiece, slides upon the inner section and carries a lens-tube b2. The latter lits into the fixed section of the tube B and is compelled to move with the outer section by a connecting-pinf, secured to the lens-tube b2 and extending' outwardly through a longitudinal slot f formed in the fixed tube-section b and into an opening' in the sliding section b, as best shown in Fig. 10. By this construction the pinfalso serves as a stop for limiting the outward movement of the sliding tube-section on the fixed section. g is a spring arranged in said fixed tube-section between its head b3 and the opposing end of the lens-tube b2 and tending to extend the sliding section 7) to its outer normal position, as shown in the drawings. The springs g allow the outer sliding tube-sections to be pushed inward on the fixed sections for shortening the eyepieces when the instrument is not in use, permitting the usual receivingcase of the Ainstrument to be made correspondingly shorter or shallower.

As shown in Figs. 8 and 4:, the objectives are out of line with or above the plane of the eyepieces. Between the objective and the eyepiece of each half of the instrument are located image-erecting prisms H H of any suitable or well-known construction, the faces of which are in the proper relation to obtain the desired reiiections. The two sets of prisms are alike, and a description of one set will apply to both. They are arranged in the casing A, and the prism H is located in the optical axis, with its upper reflecting-surface 7L in opposing relation to the objective C and its lower refiecting-surface /t in similar relation to the eye-lens B', as shown in Fig. 9. lThe other prism, H', is arranged on the inner side of the prism H, with its reflecting-surfaces if h3 opposite the respective surfaces /t /t of the latter prism. The offset prism H is movable toward and from the prism H, or, in other words, in a plane at right angles to the optical axis, for the purpose of focusing the instrument, thus effecting the focal adjustment without changing the relation between the objective and the eyepiece. This adjustment of the movable prism of each set may be effected by any suitable means. In the preferred construction shownin the drawings the movable prisms H of the two parts of the instrument are moved away from the opposing prisms by springs z', suitably secured to the rear plates of the casings A and bearing against the inner sides of the movable prisms, and the latter are shifted toward the lixed prisms by a wedge or conical nut J, engaging the screw E and bearing at opposite sides against transverse shifting pins It', projecting from the backs of the adjustable prisms and passing through the inner ends of the casings, as shown in Figs. l and 5. The nut J Y is provided in its periphery with a longitudinal groove j, which receives the outer end of one of the shifting pins In, so as to hold the nut from turning on the screw. By this construction upon turning the adjusting-screw forwardly the conical nut is caused to advance on the screw and shift the movable prisms H toward the fixed ones, while upon turning the screw in the opposite direction' said nut recedes and allows the adjustable prisms to move away from the fixed prisms under the action of their return-springs c'. Each movable Aprism is guided by a rib Z, arranged on the inner side of the rear plate A2 of the casing and fitting into a longitudinal groove Z' in the opposing side of the prism carrying plate Z2, as shown in Fig. 7.

The fixed prisms may be secured in place by any suitable means; but each of the same is preferably attached to a plate or mount m, having a collar m, which is snugly fitted in the objective-tube C. This collar is of the proper length to bear against the inner side of the .objective lens, whereby the collar performs the additional function of retaining said lens against the usual internal shoulder of the tube, as shown in Fig. 4.

According to the preferred construction of the casings A their front plates A are cast integral with their sides, While their rear plates A2 are separate and secured to the sides by screws n. (Shown in Figs. 5, 6, and 7.) In order to give the instrument a finished appearance, it is desirable to conceal the heads 'of these screws, and for this purpose the entire outer surface of each rear plate except its marginal portion is provided with a covering n, of leather or other suitable material,which is cemented to the plate. For the purpose of finishing the front plates of the casings to correspond with the rear plates a leather covering n2 is also applied to the front plates, as shown in Fig. 4. Around its edge each plate is provided with a bead or raised rib n3, which is flush with or slightly raised above the leather covering and which may be electroplated to produce a neat finish. The screwheads of the rear plate being inside of its bead and iiush with the countersunk or depressed portions of the plate are hidden by the covering 'n'.

By adjusting the prisms instead of the eyepieces or the objective for focusing the instrument the construction of the instrument is materially simplified and its cost of manufacture reduced accordingly. The improvement also permits a shorter and more compact construction of the instrument, enabling it to be held more steadily, while the arrangement of the movable prisms on the inner sides of the optical axes also contributes to the advantage of greater compactness by utilizing the central space between the eyepieces or tubes, while at the same time avoiding unsightly bulges at the outer sides of the tubes.

TOO

TIO

My improved construction has the further advantage that the adjusting devices of the prisms do not extend beyond the sides of the casings and are fully protected Yfrom injury in case the opera-glass should be dropped. These adjusting devices, while permitting the instrument to be conveniently focused, do not interfere with the hinging action of the two parts of the glass.

The elevation of the objectives above the plane of the eyepieces is also a desirable feature in that the observer when using the operaglass in a theater can better look over the heads of persons sitting in front of him.

As before stated, my improvements are also applicable to other instruments employingr telescopes, such as field-glasses, astronomical instruments, and transits and other surveying' instruments. V

Fig. 11 shows a modified construction of the invention as applied to a field-glass. In this case the objectives are mounted in drawtubes C in a well-known manner. The casings A3 are pivoted together to permit adjustment between eyepieces; but the hinge and the prism-adjusting devices are in this modification located on the rear side of the easings between the objective-tubes. Pintleeyes d are formed on parallel arms or brackets o, carried by the rear plates of the casings, and the head of the adjusting-screw E' is arranged at the rear end of the latter. The conical nut J" traverses this screw, as in the construction first described; but the pins 7c' 71:2, upon which the nut acts, instead of being attached to the movable prisms H2 are carried by shifting-levers y). These levers are pivoted at their rear ends to the brackets 0, while their free ends pass through longitudinal slots p' in the rear plates of the easings and engage with the mounts m2 of the movable prisms in such a manner that when the nut J advances on the adjusting-screw the levers p shift the movable prisms H2 toward the fixed prisms H3. The movable prisms are shifted in the opposite direction by springs, as in the firstdeseribed construction. In order to permit the optical axis of one tube of the instrument to be shortened or lengthened with relation to that of the other, if desired, one of the shifting pins--say the pinf-preferably consists of an adjusting-screw, which engages a threaded opening in the corresponding lever, as shown. As the optical axis of the fieldglass is longer than that of the opera-glass, a correspondingly greater movement of the movable prisms is required for the focal adjustment. This increased movement is obtained by em ploying the levers y), which multiply the throw or stroke of the conical nut J".

An example of the invention in connection with the telescope of a surveying instrument is shown in Fig. 12. In this view g is the pivot upon which the telescope swings. The objective and the eyepiece are of ordinary construction. H'L is the fixed prism,supported in a transverse casing A, arranged partly inside and partly outside of the main telescopetube, and I 5 is the adjustable prism, arranged in the projecting portion of the casing. The last-named prism is moved away from the fixed prism by a spring, as in the previous construction, and shifted toward the same by an adjusting-screw F42, passing through the closed outer end of the casing.

The invention is especially advantageous in such pivoted telescopes. As the focal adjustment is effected solely by moving one of the prisms. the telescope is not required to be lengthened or shortened, but always remains balanced in its bearings, thus obtaining close measurements and also preventing the ends of the telescope from striking the glass cover of the compass and causing injury or breakage of the parts, which is liable to occur in surveying instruments of ordinary construction when the telescope is lengthened. Moreover, as the relation between the eyepiece and the objective remains unchanged the line of culmination is not disturbed.

It is well known in the art that the greater the distance between the objective and the eyepiece the greater is the power of the instrument. As applied to surveying instruments my invention affords increased power within a given space or distance, because the telescope requires no terrestrial eyepiece, no draw-tube for the objective, and hence no rack and pinion for operating such a tube.

In the modification of the invention shown in Fig. 13 a push-button E" is substituted for the adjusting -screw E shown in Fig. 12. This construction permits the telescope to be focused with one hand and is therefore desirable for gun-telescopes and those used by Sportsmen.

From the foregoing description it is apparent that the invention is susceptible of various modifications without departing from its scope or spirit, and I do not, therefore, wish to be limited t'o the particular embodiments of the same herein shown and described.

I claim as my inventionl. In a telescope, the combination of an objective, an eyepiece, and opposing prisms interposed between the objective and the eyepiece, one of the prisms being located in the optical axis of the telescope and the other being movable at an angle to said axis, a spring for shifting the movable prism in one direction, and means for shifting the same in the opposite direction, substantially as set forth.

IOO

IIO

2. In an instrument of the character decated in the optical axis of the corresponding objective and eyepiece and the other prisms being located on the inner sides of the firstnamed prisms, whereby said inner prisms are arranged in the portions of the casings between the two telescope-tubes of the instrument, substantially as set forth.

3. In an instrument of the character described, the combination of a pair of connected casings each having an objective and an eyepiece which are fixed relatively to each other, a set of prisms arranged in each casing, one prism of each set being fixed and located in the optical axis of the corresponding objective and eyepiece and the other prisms being independent of the eyepieces and objectives and located on the inner sides of the firstnamed prisms and movable toward and from the same, and means for simultaneously adjusting said movable prisms, substantially as set forth.

4. In an instrument of the character described, the combination of a pair of connected casings each having an objective and an eyepiece, a set of prisms arranged in each casing, one prism of each set being located in the optical axis of the corresponding objective and eyepiece and the other prisms being movable toward and from the first-named prisms respectively and arranged on the inner sides thereof, said movable prisms being provided with shifting devices which extend through the walls of the casings, an adjusting-screw arranged between the two telescope-tubes of the instrument, and a wedge mounted on said screw and engaging said shifting devices, substantially as set forth.

5. In an instrument of the character described, the combination of a pair of connected casings each having an objective and an eyepiece, a set of prisms arranged in each casing, one prism of each set being located in the optical axis of the corresponding objective and eyepiece and the other prisms being movable toward and from the first-named prisms respectively and arranged on the inner sides thereof, shifting-levers for the movable prisms, and an adjusting-screw arranged between the two telescope-tubes of the instrument and having a wedge which engages said levers, substantially as set forth.

6. In an instrument of the character described, the combination of a pair of connected casings each having an objective and an eyepiece, a set of prisms arranged in each casing, one prism of each set being located in the optical axis of the corresponding objective and eyepiece and the other prisms being movable toward and from the first-named prisms respectively, shifting-levers for the movable prisms, an adjusting-screw having a wedge which engages said levers, and springs arranged to shift the movable prisms away from the opposing prisms, substantially as set forth.

7. In an instrument of the character described, the combination of a pair of connected casings each having' an objective and an eyepiece, a set of prisms arranged in each casing, one prism of each set being located in the optical axis of the corresponding objective and eyepiece and the other prisms being movable toward and from the first-named prisms respectively, shifting-levers for the movable prisms, one of said levers being provided with an adjustable pin or projection, an adjusting'- screw arranged between said levers, and a wedge mounted on said screw and engaging said adjustable pin and the opposing lever, substantially as set forth.

8. In an instrument of the character described, the combination of a pair of connected casings each having an objective andan eyepiece, a set of prisms arranged in each casing, one prism of each set being located in the optical axis of the corresponding objective and eyepiece and the other prisms being movable toward and from the first-named prisms respectively, shifting-levers for the movable prisms, one of said levers beingl provided with an adjustable pin or projection, an adjusting'- screw arranged between said levers and held against endwise movement, and a conical nut traversing said screw and engaging said adtially as set forth.

9. In a telescope, the combination of an eyepiece, an objective-tube having an internal shoulder and an objective-lens seated against said shoulder, prisms interposed between the `eyepiece and the objective, and a mount or support carrying one of said prisms and provided with a collar which fits into the objective-tube and holds the objective-lens against said shoulder, substantially as set forth.

l0. In a telescope, the combination of a casing, an eyepiece comprising a stationary tube or adapter secured to the casing, a shell sliding upon said adapter, a lens-tube fitting in the adapter and connected with said shell, a spring arranged within the adapter and bearing at one end against an abutment and at its opposite end against the inner end of said lens-tube, whereby the spring tends to slide the lens-tube and the shell outwardly on the adapter, and means for limiting the outward movement of the lens-tube and shell on the adapter, substantially as set forth.

11. In an instrument of the character described, the combination of a casing having a plate provided around its edge with a raised bead, and a covering applied to the depressed portion of said plate bounded by said bead, substantially as set forth.

l2. In an instrument of the character described, the combination of a casing having front and rear plates, one of which is removably secured thereto by suitable fastenings and provided around its edge with a raised bead, and a covering applied to the depressed vjustable pin and the opposing lever, substan- IOO IIO

portion of said plate and concealing said fasand concealing said faStenngS, substantially IO tenings, substantially as set forth. as set 'orth.

13. In an instrument oi' the character de- Witness Iny hand this 30th day of March, scribed, the combination of a casing having, 1904. 5 front and rear plates, one of which is remov- 1 abl7 secured thereto by suitable fastenings, p CARL B DIEGKMANN' each of said plates being provided around its lNitnesses: edge with a raised bead, and coverings ap- THEO. L. PoPr,

plied to the depressed portion of said plates EMMA M. GRAHAM. 

